Biomedical subjects

M Kirchgessner

Publications and source records attributed to M Kirchgessner.

At least 55 records · Page 3Linked to original sources

PubMed1996

A study on the nutritive value of pollen from the Chinese Masson Pine (Pinus massoniana) and its effect on fecal characteristics in rats.

A digestion experiment with growing rats was conducted to study the effect of native and broken pollen of Chinese Masson Pine (Pinus massoniana) on fecal composition and digestibilities of dry matter, crude protein and crude ash. For that issue each 10 of 30 animals were fed a semisynthetic diet containing either no pollen or and addition of 6% native or broken pollen for 17 days at restricted amounts. In a second experiment each 6 of 12 growing rats received a semisynthetic diet containing either no or 5% broken pollen. At day 4, 11 and 18 samples of the feces were collected and analyzed for mesophilic aerobic bacteria. The pollen contained large amounts of cell wall constituents (26-30% lignin and 10-15% cellulose, 2-13% hemicellulose) with higher values found in native pollen. The contents of crude protein, crude fat, total lipids, available carbohydrates (starch and sugars), crude ash, gross energy and metabolizable energy were 13%, 2-10%, 8-10%, 17-18%, 3.1-3.5%, 21-22 kJ/g and 5.7-9.0 kJ/g. The addition of native pollen to the diet increased the total amount of feces by 71% as compared to the control level. The fecal contents of dry matter and of crude protein and crude ash in fecal dry matter changed by -5, +4 and -5 percentage units. The apparent digestibilites of dry matter and crude protein decreased by 3 and 5 percentage units, respectively, while the apparent digestibility of crude ash remained unchanged. Broken pollen acted in the same direction, however the effects were about 20% less pronounced as compared to native pollen. The pollen feeding reduced the fecal germ contents of Proteus mirabilis and Escherichia coli, while the amounts of alpha-hemolysing streptococci was increased. In total, the observed effects of an addition of native broken or pollen to the diet seemed to be based mainly on the increased intake of cell wall constituents.

Animals↗

PubMed1996

[The effect of different vitamin B6 supplies on the vitamin B6 status (pyridoxine, pyridoxal and pyridoxamine) of the liver and the body of lactating rats].

Eighty female Sprague-Dawley rats were fed a semisynthetic diet during gravidity which was supplemented with 5 mg vitamin B6 per kg diet. The daily food intake was 14 g. During the following lactation the rats were assigned to one of 10 vitamin B6 treatment groups (0, 3, 6, 9, 12, 15, 18, 36, 360 and 3,600 mg per kg diet). The feed was given ad libitum. At day 14 of lactation the rats were decapitated. Parameters for determination of the vitamin B6 status were concentration of pyridoxine, pyridoxal and pyridoxamine in liver and body analyzed by using HPLC. Body was defined without the gastroenteral tract that was divided into carcass (extrahepatic compartments without liver) and total body (extrahepatic compartments plus liver). The mean weight of liver was 13 g with a dry mass of 33%; there was no difference between the treatment groups. The vitamin B6 concentration was lowest in rats fed 0 mg vitamin B6/kg diet (5 micrograms/g fresh matter, FM) and highest in the rats fed 3600 mg vitamin B6/kg diet (10.9 micrograms/g FM). The total vitamin B6 consisted on the average of 38% pyridoxal and 62% pyridoxamine. This was only changed significantly at the highest supplementation level, where 20% pyridoxine were detected instead of pyridoxamine. The mean weight of carcass averaged 212 g at a dry matter content of 31%. The vitamin B6 concentration ranged in the treatment groups from 0 mg to 360 mg vitamin B6/kg diet between 2.1 micrograms/g FM and 2.8 micrograms/g FM. It was highest in the 3600 mg vitamin B6 treatment group at 7.5 micrograms/g FM. The total vitamin B6 consisted of 63% pyridoxal and 37% pyridoxamine. It was only significantly affected in the 3600 mg vitamin B6 treatment group, where also pyridoxine could be found in the amount of 56%. The results indicate that alimentary vitamin B6 supply had more influence on liver vitamin B6 concentration than on carcass concentration. Total body concentration is very similar carcass concentration, as 95% of vitamin B6 is located there. The suitability of the parameters by the evaluation of the vitamin B6 requirement was confirmed the comparison of two statistical methods. It is concluded that a vitamin B6 supply of 5 to 6 mg/kg diet is necessary to meet the requirements during lactation.

Animals↗

PubMed1996

[The effect of alimentary vitamin B6 supply during pregnancy and lactation on the activity of specific transaminases of lactating rats].

Eighty female Sprague-Dawley rats weighing 257 g were fed during gravidity a semi-synthetic diet containing five vitamin-B6-treatment groups (0.6, 3, 6, 18 and 180 mg/kg diet). The daily food intake was 14 g. During the following lactation the rats of each treatment group were divided into two groups containing 3 and 6 mg vitamin B6. At the 14th day of lactation the dams were decapitated. Parameters for determination of the vitamin-B6-status were activity of AST and ALT in plasma, erythrocytes and liver. The average activity of AST in plasma was 549 U/l, in erythrocytes 1939 U/l and liver 106 U/g fresh matter (FM). The increasing vitamin-B6-supplementation during gravidity resulted in an elevated activity of AST between lowest and highest treatment group in plasma 56%, erythrocytes 44%, and in liver 43%, respectively. In response to the increasing vitamin-B6-treatment during lactation the activity of AST in plasma increased for 19%, in erythrocytes for 13%, and in liver for 24%, respectively. A low vitamin-B6-supply (0.6 mg/kg diet) during gravidity in combination with demand-oriented supply during lactation (6 mg/kg diet) initiated the highest increase of activity. A deficient vitamin-B6-supply during lactation (3 mg/kg diet) could be compensated with optimal vitamin-B6-supply during gravidity. The values of ALT-activity showed no significant differences between the graded vitamin-B6-supplements, as a result of a high coenzyme saturation.

Alanine Transaminase↗

PubMed1996

Concentrations of thyroid hormones in serum and activity of hepatic 5' monodeiodinase in copper-deficient rats.

The aim of the present study was to investigate the effect of copper deficiency on thyroid hormone metabolism in rats. Therefore, an experiment with growing male Sprague-Dawley rats was carried out, consisting of two groups of rats fed either a copper-deficient (0.06 mg Cu/kg) or a copper-adequate diet (16 mg Cu/kg). Both groups of rats were fed identical quantities of diet by pair-feeding. Copper deficiency decreased the final body weight of the rats by 5% compared to copper-adequate control rats. A severe copper-deficient state in the rats fed the copper-deficient diet was proved by a large decrease of ceruloplasmin activity in serum (by 97%) and hematological changes. For estimation of thyroid hormone metabolism, the concentrations of total and free thyroxine (T4) and triiodothyronine (T3) in serum and the activity of hepatic 5'monodeiodinase (5'D) were determined. Copper-deficient rats had an increased concentration of T3 in serum, whereas the concentrations of total and free T4 as well as the activity of hepatic 5'D were not different compared with copper-adequate control rats. Therefore, the study shows that copper deficiency has only slight effects on thyroid hormone metabolism in growing rats.

Anemia↗

PubMed1996

[Hematologic changes in alimentary Pb deficiency in growing rats].

The effect of an alimentary Pb-deficiency on hematological parameters was examined in two growth- and one generation-experiments with female Sprague Dawley rats. The animals were fed a semisynthetic casein-based diet supplemented with 0 ppb up to 800 ppb Pb as Pb-II-acetate-3-hydrate. In two experiments the blood parameters of the rats of G0-generation fed the diet poor in Pb were changed to a normocytic, normochrome pancytopenia at day 21 resp. 28 of the experiments. At day 28 resp. 41 the blood parameters normalized resp. the different Pb-supply in the diet only effected the mean corpuscular volume- and mean corpuscular hemoglobin-values. It was assumed that the disturbances in blood parameters at deficient Pb-supply are caused by temporary hemolysis.

Animals↗

PubMed1996

Subcellular distribution of protein kinase C (pKC) in erythrocytes and concentration of D-myo-inositol-1,4,5-trisphosphate (IP3) in platelets and monocytes of force-fed zinc-deficient rats.

The purpose of the present study was to investigate whether alimentary zinc (Zn) deficiency affects the activities of the Zn metalloenzymes protein kinase C (pKC) and the phosphatidylinositol-specific phospholipase C (PLC) in force-fed Zn-deficient rats. The in vivo activity of pKC was determined by measuring the subcellular distribution of the enzyme between the cytosolic and the particulate fraction of erythrocytes, whereas the activity of PLC was measured indirectly through the concentration of its metabolite inositol-1,4, 5-trisphosphate (IP3) in platelets and monocytes. For this purpose, 24 male Sprague-Dawley rats with an average live mass of 126 g were divided into 2 groups of 12 animals each. The Zn-deficient and the control rats received a semisynthetic casein diet with a Zn content of 1.2 and 24.1 ppm, respectively. All animals were fed the same amount of the diet (10.8 g dry matter [DM]/d and rat) four times daily by gastric tube. After 12 d, the depleted rats were in a state of severe Zn deficiency, as demonstrated by a 70% lower Zn concentration and a 66% reduction in the serum activity of alkaline phosphatase. The radio-immunologically determined concentration of IP3 was reduced by a significant 55% in the platelets of the Zn-deficient rats (8.4 pmol IP3/ 5 x 10(8)) as compared with the control rats (18.8 pmol IP3/5 x 10(8)), whereas the IP3 concentration in the monocytes was not affected by the alimentary Zn supply (1.4 vs 1.2 pmol IP3/10(6)), nor was there any difference between the Zn-deficient and the control rats with regard to the radioenzymatically determined specific activity of pKC, either in the cytosolic fraction (32.7 vs 32.5 pmol P/min/mg protein) or in the particulate fraction (38.1 vs 36.5 pmol P/min/mg protein) of the erythrocytes.

Animals↗

PubMed1996

Zinc deficiency and the desaturation of linoleic acid in rats force-fed fat-free diets.

Recent studies with rats force-fed zinc-deficient diets containing various types of fat failed to demonstrate a role of zinc in desaturation of linoleic acid. The present study was conducted to investigate the effect of zinc deficiency on desaturation of linoleic acid in rats that were initially force-fed fat-free diets to stimulate activity of desaturases. Therefore, rats were fed zinc-adequate and zinc-deficient fat-free diets for 6 d. After that period, the groups were divided and half of the rats continued feeding the fat-free diet for another 3.5 d whereas the other half was switched to a fat diet by supplementing the fat-free diet with 5% safflower oil. In order to assess desaturation of linoleic acid, fatty acid compositions of liver phosphatidylcholine, -ethanolamine, and -serine were considered, particularly levels of individual (n-6) polyunsaturated fatty acids (PUFA). Levels of total and individual (n-6) PUFA were similar in zinc-adequate and zinc-deficient rats fed the fat-free diet throughout the experiment. Addition of 5% safflower oil increased levels of total and individual (n-6) PUFA in both zinc-adequate and zinc-deficient rats. However, total (n-6) PUFA in all types of phospholipids were higher in zinc-adequate rats than in zinc-deficient rats. Additionally, in zinc-deficient rats there were changes of (n-6) PUFA levels typical for impaired delta 5 and delta 6 desaturation: linoleic acid and dihomo-gamma-linolenic acid were elevated; arachidonic acid, docosatetraenoic acid, and docosapentaenoic were lowered by zinc deficiency. Therefore, the study shows that zinc deficiency impairs desaturation of linoleic acid in rats force-fed fat-free diets and therefore supports results from former convential zinc deficiency experiments suggesting a role of zinc for desaturation of linoleic acid.

Analysis of Variance↗

PubMed1996

Activity and subcellular distribution of protein kinase C (PKC) in muscle and brain of force-fed zinc-deficient rats.

The purpose of the present study was to investigate, in force-fed rats, whether alimentary zinc (Zn) deficiency affects the activity of the Zn-metalloenzyme protein kinase C (PKC). The in vivo activity of PKC was determined by measuring the subcellular distribution of the enzyme between the cytosolic and the particulate fraction in brain and muscle. For this purpose, 24 male Sprague-Dawley rats with an average live mass of 126 g were divided into 2 groups of 12 animals each. The Zn-deficient and the control rats received a semisynthetic casein diet with a Zn content of 1.2 and 24.1 ppm, respectively. All animals were fed four times daily by gastric tube in order to ensure that the depleted animals also received adequate nutrients and to synchronize the feed intake exactly. After 12 d, the depleted rats were in a state of severe Zn deficiency, as demonstrated by a 70% lower serum Zn concentration and a 66% reduction in the serum activity of alkaline phosphatase. Neither the cytosolic nor the particulate fraction of the thigh muscle showed any difference between the depleted and the control animals as regards PKC activity/g of muscle. The specific activity of PKC/mg of protein in the cytosolic fraction of the muscle was not affected by alimentary zinc deficiency, whereas the specific activity of PKC in the particulate fraction of the muscle was reduced by a significant 10% in Zn deficiency (150 +/- 12 vs 135 +/- 14 pmol P/min/mg protein). In the brain, neither the cytosolic nor the particulate fraction revealed any difference in PKC activity/g of fresh weight or in the specific activity/mg of protein between the control and the Zn-deficient rats.

Animals↗

PubMed1996

Influence of alimentary zinc deficiency on the concentration of the second messengers D-myo-inositol-1,4,5-trisphosphate (IP3) and s,n-1,2-diacylglycerol (DAG) in testes and brain of force-fed rats.

The phosphatidylinositol-specific phospholipase C, presumably a Zn-metalloenzyme, catalyzes the hydrolysis of phosphatidylinositol-4,5-bisphosphate to inositol-1,4,5-trisphosphate (IP3) and s,n-1,2-diacylglycerol (DAG). The activity of phosphatidylinositol-specific phospholipase C was measured indirectly by determination of the metabolites IP3 and DAG in Zn deficiency. For this purpose 24 male Sprague-Dawley rats with an average live mass of 117 g were divided into 2 groups of 12 animals each. The Zn-deficient and the control group received a semisynthetic casein diet with a Zn content of 1.6 ppm and 115 ppm, respectively. In order to prevent the reduced feed intake that occurs in Zn deficiency and the associated energy and protein depletion from interfering with the experimental parameters, all animals were fed four times daily by gastric tube. This made it possible to supply all animals with adequate nutrients and to synchronize the feed intake exactly. After 12 d, the depleted rats were in a severe state of Zn deficiency, as demonstrated by the reduction of Zn in the serum and the femur by 74% and 43%, respectively, and the 28% lower serum activity of alkaline phosphatase. The radioimmunologically determined concentrations of IP3 were reduced by a significant 53% in the testes of the Zn-deficient rats (0.24 nmol IP3/g wet wt) compared to the control animals (0.51 nmol IP3/g wet wt), while the IP3 concentration in the brain was not affected by the alimentary Zn supply (1.7 and 1.6 nmol IP3/g wet wt, respectively). The DAG concentrations in the testes (474 vs 471 nmol DAG/g wet wt) and the brain (594 vs 640 nmol DAG/g wet wt), which were determined by radioenzymatic methods, showed no significant differences in relation to the alimentary Zn supply. The fact that the Zn concentration in the Zn-deficient rats was reduced only in the testes and not in the brain and that high concentrations of DAG may also result from other metabolic processes suggests that the phosphatidylinositol-specific phospholipase C in the mammalian organism is a Zn-metalloenzyme whose activity is reduced in alimentary Zn deficiency in tissues suffering Zn loss.

Animals↗

PubMed1996

Influence of zinc and selenium deficiency on parameters relating to thyroid hormone metabolism.

48 weaned male Sprague-Dawley rats with an initial average body weight of 41 g were divided into 4 groups of 12 animals (zinc-deficient; zinc-adequate, pair-fed with zinc-deficient group; selenium-deficient; selenium-adequate) for 40 days. All groups were fed a semisynthetic diet with casein being the source of protein. In the selenium-deficient diet, there was a selenium concentration of 0.038 mg/kg. The other diets were supplemented with Na-selenite in order to adjust the selenium concentration to 0.3 mg/kg. In the zinc-deficient diet, there was a zinc concentration of 4.1 mg/kg. The zinc concentrations in the other diets were adjusted to 45 mg/kg by the addition of zinc-sulfate heptahydrate. Zinc-deficient rats were characterized by a markedly reduced alkaline phosphatase activity in their serum, whilst selenium-deficient rats showed a markedly reduced glutathione peroxidase in serum proving their respective zinc-deficient and selenium-deficient states. Zinc deficiency decreased concentrations of triiodothyronine (T3) and free thyroxine (fT4) in serum by approximately 30% when compared with zinc-adequate controls. The concentration of thyroxine (T4) in serum was not affected by zinc deficiency. Selenium-deficient animals had lower concentrations of T3 and T4 than selenium-adequate animals. The concentration of fT4 in serum was not affected by selenium deficiency. The activity of hepatic type I 5'deiodinase was decreased by 67% by zinc deficiency and by 47% by selenium deficiency compared to adequate controls. The study data show that both zinc and selenium deficiency affect the metabolism of thyroid hormones.

Amino Acids↗

PubMed1996

[The effect of enzyme supplements and high amounts of white lupins on concentrations of lipids in serum and meat in fattening chickens].

A bi-factorial experiment was conducted to investigate the effect of enzyme supplements (200 mg Roxazyme G per kg feed) and white lupins (35%, freshly harvested or stored) on concentrations of lipids in serum and lipoproteins as well as in chest and leg meat. Enzyme supplements had not any effect on concentrations of cholesterol, triglycerides and phospholipids in serum and lipoproteins and on concentrations of triglycerides and cholesterol in meat. In contrast, feeding the rations with 35% lupins lowered concentrations of triglycerides and phospholipids in serum as well as concentrations of total cholesterol, triglycerides and phospholipids in high-density lipoproteins. However, freshly harvested and stored lupins partially had different effects on those parameters. Lipids in low-density lipoproteins were not affected by lupins. Feeding the rations with 35% lupins increased triglyceride concentrations in thigh muscle whereas triglyceride concentration in chest muscle as well as cholesterol concentration in both pieces were not changed. Clinical-chemical parameters related to protein metabolism were not affected by either enzyme supplements or lupins.

Animal Feed↗

PubMed1996

[The effect of the live weight of rats on the intestinal in vitro absorption of nickel using everted intestinal sacs].

The influence of the live weight of the experimental animals on the Ni absorption was investigated in vitro with everted sacs from rats. Totally 75 male rats in the live weight range from 30 to 250 g were used. With increasing live weight the Ni uptake by the intestinal wall and the Ni transfer across the intestinal wall decreased significantly. Ni transfer was already significantly reduced by 45% when body weight increased from 30 to 60 g. For the animals with a live weight above 200 g Ni transfer reached only about 10% of the Ni transfer measured for the animals with 30 g live weight. The decline of the Ni uptake by the intestinal wall was only slightly in the live weight range from 30 to 150 g. Within the live weights higher than 190 g Ni uptake by the intestinal wall decreased significantly to about 25% compared to the animals with 30 g live weight.

Animals↗

PubMed1996

Effect of feeding various dietary vitamin B6 concentrations during gestation and lactation on vitamin B6 level in liver and carcass of rat dams.

The present investigation was designed to determine the vitamin B6 concentration in liver and carcass of rat dams fed various dietary vitamin B6 levels during gestation and lactation. Therefore, gravid female rats received 0.6, 3, 6, 18 or 180 mg vitamin B6 per kg diet. After parturition each group was divided into 2 groups of 8 dams each, which received then a diet with 3, respectively 6 mg/kg vitamin B6 during lactation. At the end of the experiment at day 14 of lactation weight gain and food consumption as well as liver and carcass weights did not differ within the groups. The present data clearly show that both in liver and carcass of lactating rats, there exists only a slight dose-response-relationship between the dietary vitamin B6 intake and the vitamin B6 concentration in body tissue. Moreover, liver reflects the various vitamin B6 supplies during gestation and lactation somewhat better than carcass. The distribution of the vitamins did not differ among the groups and was therefore independent of the vitamin B6 supply. The present findings, especially regarding the liver, elucidate, that an adequate vitamin B6 supply during lactation can not compensate for a lack of vitamin B6 during gestation and vice versa a high dose of vitamin B6 during gestation did not completely protect against a suboptimal vitamin B6 during lactation.

Animals↗

PubMed1996

[Feed intake and performance of dairy cows during feeding of fodder beets supplementing grass silage].

In a feeding experiment 3 x 12 dairy cows (German Simmental x Red Holstein Friesian) were used to investigate the influence of different amounts of fodder beets on feed intake, milk yield and milk composition. The fodder beets (variety Kyros) were fed in exchange for concentrate. The amounts of fodder beets were either 22 kg cow-1 d-1 or 44 kg cow-1 d-1 or zero (control group). All groups received 4 kg hay cow-1 d-1, grass silage ad libitum, and concentrate corresponding to the milk yield. In order to balance the rations the concentrate was either rich in protein or rich in energy. Feeding 22 kg or 44 kg fodder beets increased forage intake (including fodder beets) significantly. However, the total feed intake diminished on average from 18.3 kg DM cow-1 d-1 (control group) to 17.2 kg DM cow-1 d-1 (fodder beet groups). In each treatment the intake of hay was 3.3 kg DM cow-1 d-1. However, the intake of grass silage offered ad libitum was significantly suppressed by the fodder beets. Considering the different amounts of concentrate the quantity of suppression of grass silage by feeding fodder beets was calculated at -0.8 kg DM of grass silage per kg DM of fodder beet intake. The milk yield decreased linearly with increasing fodder beets on average up to 4 kg cow-1 d-1. However, the milk composition was scarcely influenced. The fat content increased a little, the mean alterations of the protein and lactose content were below 0.1 percentage points. Therefore, the change in daily excretion of milk fat, protein or lactose were similar to the change in milk yield. In conclusion, feeding fodder beets in combination to grass silage causes a positive effect on forage intake (including fodder beets). However, the amount of concentrate should not be reduced equivalently to the energy contents of the added fodder beets.

Animal Feed↗

PubMed1996

[The effect of starch-rich single feed on the digestibility and the energy content of corn silage in cattle and sheep].

Different starch components were added to rations with maize silage measuring the influence of the supplements on the digestibility and energy content of maize silage in cattle (n = 36) and sheep (n = 36). The starch-rich components maize, wheat, barley, oat, cassava meal and potato starch were added to the total rations on average of 33%. All supplements were ground (sieve of 2.5 mm); additionally, wheat was added in extruded or crushed form. All rations including the control ration without starch components were supplemented with soybean meal to an average crude protein content of 12.4% DM. The mean starch content of the total rations was 42% DM. The supplementation of maize silage with the different starch components increased the digestibility of the organic matter of all rations on average only slightly from 77% to 78% in cattle, while the mean digestibility in sheep raised from 74% to 79% more pronounced. However, the influence of the different starch components on the digestibility was similar for both ruminants. The supplementation with the ground, crushed or extruded wheat, with barley and with oats impaired the digestibility of the crude fibre of the total ration and of the maize silage, respectively. Therefore, the digestibility of the organic matter of maize silage was reduced and the energy content decreased by about 6% in comparison to the control ration without starch supplementation. However, the supplementation with maize, cassava meal or potato starch had no negative effects on the digestibility and energy content of maize silage.

Animal Feed↗

PubMed1996

Nickel deficiency alters liver lipid metabolism in rats.

The present investigation was designed to examine the effect of nickel deficiency on lipid metabolism in liver and serum lipoproteins of rats. Therefore, a study over two generations was conducted feeding a nickel-deficient diet containing 13 microg/kg nickel or a nickel-adequate diet supplemented with 1 mg/kg nickel. Male 7-wk-old pups from the second offspring were studied. Pups fed a diet poor in nickel tended to have lower weight gains (P < 0.15), nickel concentrations in liver (P < or = 0.1) and iron levels in serum (P < 0.1) than nickel-adequate rats. They were classified as nickel-deficient on the basis of significantly lower erythrocyte counts, hemoglobin concentrations, hematocrits and nickel concentrations in kidney compared with nickel-adequate rats. Nickel deficiency caused a significant triacylglycerol accumulation in liver, with greater concentrations of saturated fatty acids, monounsaturated fatty acids, and polyunsaturated fatty acids than nickel-adequate rats. Nickel deficiency had slight but significant effects on the fatty acid composition of liver total lipids and phosphatidylcholine and phosphatidylethanolamine. Moreover, nickel-deficient rats had significantly lower activities of the lipogenic enzymes glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, malic enzyme and fatty acid synthase than nickel-adequate rats. Nickel-depleted pups had significantly higher concentrations of triacylglycerols and phospholipids in serum VLDL, and cholesterol in serum LDL than nickel-adequate pups. Most of these alterations in lipid metabolism are similar to those obtained in several iron-deficiency studies. Because nickel deficiency also slightly compromised iron status, it is possible that at least some of the observed alterations are due to the moderate iron deficiency.

ATP Citrate (pro-S)-Lyase↗

PubMed1996

Effect of Hay's separation principle on the energy metabolism.

A cross-over experiment was conducted with 8 adult, nonpregnant sows in order to test whether feeding according to the principle of Hay's separation diet exerts a stimulant effect on thermogenesis. The protein part of the daily ration was offered at the morning feeding, the other ration components in equal amounts at two further feedings. The control group received the daily ration in three equal portions. The levels of all nutrients in the rations matched the maintenance requirement based on the initial weight of the sows and remained unchanged throughout the experiment. In both 3-week metabolism periods a complete balance was undertaken for each animal using the collection technique (feed, feces, urine) and 48-hour measurement of the gas exchange in a respiration chamber. The body weight of the sows fed the separation diet was 178.3 kg and that of the control 178.6 kg. Oxygen and carbon dioxide were reduced by 1.5% with separation. The respiratory quotient remained unchanged. The experimental treatment had no effect on energy digestibility and metabolizability. Heat production of the animals on the separation diet was 20.6 versus 20.1 MJ/day on the control diet. The result was reversed for energy retention, namely 0.6 versus 0.0 MJ/day. The daily energy exchange profile, represented by thermogenesis plotted at 5-min intervals, showed slightly lower values than the control after the protein meal and only random differences between the two treatments for the remainder of the day. It can be concluded from the results that separation of the protein and carbohydrates in the diet within 1 day, rather than stimulating thermogenesis, is more likely to reduce it.

Animal Nutritional Physiological Phenomena↗

PubMed1996

Influence of different dietary vitamin B6 supply during gravidity and lactation on total vitamin B6 concentration (pyridoxine, pyridoxal and pyridoxamine) in blood and milk.

In a two factorial trial with 80 (5 x 2 x 8) Sprague-Dawley rats weighing 257 g the influence of different dietary vitamin B6 supply on concentration in blood and milk was examined. The two factors were 5 doses of alimentary vitamin B6 supply during pregnancy (0.6, 3, 6, 18, and 180 mg vitamin B6 per kg diet) and 2 doses in lactation (3 and 6 mg vitamin B6 per kg diet). The rats were fed a semisynthetic diet. The daily food intake was 14 g during pregnancy and ad libitum during lactation. At day 7 and 13 of lactation the dams were milked and at day 14 the animals were killed by decapitation. Vitamin B6 concentration of milk at 7th and 13th day of lactation and vitamin B6 concentration of blood at 14th day of lactation were examined. The mean total vitamin B6 concentration in blood was 0.18 microgram/ml and consisted of 94.8% pyridoxal and 5.2% pyridoxamine. An elevation in vitamin B6 supply during pregnancy led to an increase in blood vitamin B6 concentration of 40% and the vitamin B6 treatment during lactation caused an increase of 50%. The mean total vitamin B6 concentration in milk at the 7th day of lactation was 0.35 microgram/ml and consisted of 79.5% pyridoxal, 15.6% pyridoxamine and 4.9% pyridoxine. An elevation in dietary vitamin B6 supply during pregnancy led to an increase in milk vitamin B6 concentration of 79% and vitamin B6 treatment during lactation led to an increase of 38%. The mean total vitamin B6 concentration in milk at the 13th day of lactation was 0.44 microgram/ml and consisted of 79.8% pyridoxal, 13.9% pyridoxamine and 6.3% pyridoxine. Milk vitamin B6 concentration was increased by 53% through the dietary supply during pregnancy and by 32% through the higher lactational supply. The experiments indicate that vitamin B6 concentration in blood and milk is a reflection of dietary supply, whereby in lactation milk concentration is less influenced than blood.

Analysis of Variance↗